Familiar words spring to mind when users create their search queries. If your writing favors made-up terms over legacy words, users won’t find your site.
“Speak the user’s language” has been a primary usability guideline for more than 20 years. The fact that the Web is a linguistic environment further increases the importance of using the right vocabulary.
Lees meer op de pagina van Jacob Nielsen
http://www.useit.com/alertbox/search-keywords.html